Barrier methods

Condom (latex)

Condoms are the only contraceptive method that also give good protection from STIs (sexually transmitted infections).

Even if you have reliable contraception to protect against unintended pregnancy, you may also need condoms for protection from STIs.

The condom is a latex rubber sheath that is rolled on to the erect penis just before sex and removed before the penis has had time to relax. There is now a whole variety of condoms and they can be purchased from pharmacies, supermarkets, service stations and other outlets. Some brands can be prescribed free by a doctor and this is the cheapest way of getting condoms.

Failure is usually due to not using the condom on every occasion or not taking emergency contraception after an accident. Even if used correctly there is still a small failure rate of about 2-4 pregnancies per 100 couples using the method over a year.

Non-latex condoms

Occasionally you or your partner may have an allergic reaction either to the latex of a rubber condom, or to the chemicals that are used in the manufacture of the condom, or to the substances like colourings and flavourings that are sometimes added to condoms.

Changing brands will sometimes help but if it is a true latex allergy then non-latex condoms will be needed. They are a little more expensive than latex condoms.

Their reliability is about the same as latex condoms and is dependent on the care with which they are used.

Female condom

The female condom or vaginal liner is another non-latex device, available for purchase from the Family Planning website. Modern female condoms (brand name FC2) are now made of nitrile. They are non-allergenic and can be used with water-based or oil-based lubricants. The female condom has an inner ring which is floating free. This just helps insertion. It has an outer ring which is attached to the rim of the condom and rests on the woman's genital area. Like the male condom they provide good protection from sexually transmitted infections. The female condom has about the same failure rate as the male condom and like the male condom this depends on how carefully it is used.

Diaphragm and spermicide

This is an older method which is still useful when women are unable or unwilling to use hormonal methods.

The diaphragm is a rubber dome that is fitted within the vagina and covers the cervix acting as a barrier to sperm. The correct size must be fitted by a doctor or nurse experienced in the method. Spermicide jelly is applied to the diaphragm before use.

The diaphragm is inserted before sex and left in place for six to eight hours after sex. If necessary it can safely be left in for longer. After removal the diaphragm is washed and dried. With care it will last for two years.

The failure rate is higher in new users and in younger women who are more naturally fertile. Average figures range from 2-20 per 100 women using the method over a year.

Since 2010 the availability in New Zealand of diaphragms is limited and spermicide is nil. Supplies may be sourced from the internet. Try expresschemist or talk to your doctor about other methods.